Contributions to the knowledge of Leucosiidae V. Coleusia gen. nov. (Crustacea: Brachyura)

A new genus, Coleusia, is established for Leucosia species with segments 3-5 of the male abdomen fused, the shaft of the male’s first pleopod coiled thrice on its axis, bearing distally a setose lobe and an elongate apical process: L. biannulata Tyndale-Biscoe & George, 1962, L. magna Tyndale-Biscoe & George, 1962, L. signata Paulson, 1875, and L. urania (Herbst, 1801), and a new species: C. rangita. The species are described or redescribed and illustrated, extended synonymies are given, and a key for their identification is provided.